For service and parts needs, visit your dealer. You will receive genuine GM parts and GM-trained and supported service people.
Genuine GM parts have one of these marks:

Vehicle Care
California Proposition 65 WarningTest Probe Caution
Caution: Do not insert test equipment probes (DMM etc.) into any
connector or fuse block terminal. The diameter of the test probes will
deform most terminals. A deformed terminal will cause a poor connection, which
will result in a system failure. Always use the EL-35616
GM-Approved Terminal T ...
Safety Belt Extender
If the vehicle's safety belt will fasten around you, you should use it.
But if a safety belt is not long enough, your dealer will order you an extender.
When you go in to order it, take the heaviest coat you will wear, so the extender
will be long enough for you. To help avoid personal inju ...
Electrical System Overload
The vehicle has fuses and circuit breakers to protect against an electrical system
overload.
When the current electrical load is too heavy, the circuit breaker opens and
closes, protecting the circuit until the current load returns to normal or the problem
is fixed. This greatly reduces the c ...